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[KD6VXI]

Thought you guys were limited to 2200 watts.

"(ii) 750 W carrier power for transmitters that produce any other type of emission."

Which, in the case of my transmitter, would equate to nearly 4kw pep.

--Shane
WP2ASS / ex KD6VXI

"ERP is created with the dryer socket."

[VR2AX]

Some places EMF compliance 'guidelines' (aka..) will impose a limit lower than the basic power limit, likely to be more significant as you get into the V/UHF range (including 6/4 metres).

[K4IBC]

What kind of electrical service will this amp require?

[VE7RF]

What kind of electrical service will this amp require?

80 amps.  Typ 100 amps is used.   A 100 amp breaker eats up 4 x slots in the 200 amp main panel.
On SSB / CW, 60/70 amps will work just fine, and only eats up 2 x slots.  We used a  60 amp 2 pole breaker on buddy's  YC-156 80-10 amplifier.... fed with 6 ga wire,  but the HV supply is only 3' from his main 200 amp panel... but that YC-156 amp only does 7-8 kw pep out.  Bottom line is, you require 200 amp service coming into the home.

If measuring the current, be careful. Only a true RMS AC current clamp on device will work. Or an Iron vane  style panel meter with correct  external  XXX- 5 amp xfmr.   Reason is, on any C input  B+ supply,  current is drawn in pulses...every 8.3 msecs.   NON  rms current metering wants to see a true 60 hz  sinewave...not pulses every 8.3 msecs...(with each pulse lasting just 2-3 msecs).

Non  rms metering will result in readings that are 20-40%  lower than reality.  I have a 0-300 amp, clamp on...that plugs into my small Fluke 87  DVM (true rms meter).  DVM is switched to read vac.   300 amps = 3.0 vac on the DVM.  100 amps = 1.00 vac on the dvm.  50 amps = .50 vac.  10 amps = .1 vac.   The fluke 87 is a true rms dvm...and that's for both ACV..and also AC current.

On  ssb,  you won't flicker any lights. The biggest issue with these bigger amplifiers is the V drop from the street.  On buddy's  3x6 amp, with 12 kw out, key down, he loses 6 vac  from the street..and another 2 vac (main 200 amp panel to HV supply, which is 20' away)..and fed with 2 ga wire).  Basically we are dealing with un regulated  B+ supplies.  This is why taps are used on the pri of the plate xfmr. If your incoming line V measures 240 vac, the 235/230 tap is used.  If your incoming line V is 250, use the 240 tap.    My Dahl is tapped at 198-208-218-230-240-250.  If I had to do it again, I would have gotten it tapped at  220-225-230-235-240-245.

Your real no load B+ is what the HV meter reads..when sucking normal idle current.  You have to draw idle current 1st... before drive can be applied.  I could care less what the B+ is on  RX.

[VE7RF]

Thought you guys were limited to 2200 watts.

"(ii) 750 W carrier power for transmitters that produce any other type of emission."

Which, in the case of my transmitter, would equate to nearly 4kw pep.

--Shane
WP2ASS / ex KD6VXI

"ERP is created with the dryer socket."

And that's measured at the feedpoint of the ant...after feedline loss.   Folks in the US got screwed when they changed the regs years ago.   Back then, it was 1 kw dc input... which was typ 800 watts output of cxr (class C)..and 4-5 times that for pep output.

[VE7RF]

Some places EMF compliance 'guidelines' (aka..) will impose a limit lower than the basic power limit, likely to be more significant as you get into the V/UHF range (including 6/4 metres).

True.  But that's all based on average PO, and averaged over time.

[KD6VXI]

A 100A breaker eating up 4 slots is dependent on the breaker panel and the breaker used.

I have a Square D 100A breaker sitting on my desk right now that's 100A and eats up 3 slots (3 phase power).  I have another in another panel that's 100A that's two slots.  These are QO style breakers which are installed with screw terminals, but I also have some that are plug in.

I like the 4 pole 100A split phase breakers a lot more than the 2 poles, especially with residential.  Rezzy panels are junk in a lot of cases.  Eaton makes a 2 pole 100A breaker that is UL listed to go in almost any panel mfg it will fit in.  Insanity.  Problem with the 4 pole breakers is in some cases you end up having to use 'twin up' breakers (2 breakers on one slot), which to me isn't the best thing to do either.  I've walked in to some situations where the contractor cheaped out and used a 12 slot panel.  Every slot had twin up breakers in it.  Sad when I have to tell a homeowner it's going to cost another thousand to 2500 dollars to put a new panel in when they need to upgrade, install a sub panel in the garage, etc.  But, the contractor saved 40 bucks, so !PROFIT!

Have your buddy with the voltage drop measure drop from the incoming side of the main breaker to the output of the breaker feeding the amplifier, under load.  I've seen situations where there is a volt or more drop.  That's when you know it's time to change out the panel.  And for anyone running QRO with tubes with handles, the only option I will recommend is QO style Square D bolt ons.  They are more expensive, but they have compression connections, way better than 'stab in' residential crap.


--Shane
WP2ASS / ex KD6VXI

[K6BRN]

To the nay-sayers, this is where TUBE amps are going.  And with a life expectancy of 30K hours of continuous operation, if the new owner is 30 years old he will never need to replace the tube in his lifetime. 

Giving a 30 year-old a 10KW 6M high voltage amplifier built on the cheap out of surplus parts is a little like giving a 14-year-old a rusty WWII surplus grenade launcher and saying "Have at it!" in a busy neighborhood.

It this REALLY a good idea?  What will it really be used for?  And given the infrastructure needed to support it (antenna+feedline+power for 10 KW) and its lack of band agility, how useful IS it, really?

It'd be more interesting to shoehorn a Viper V10 into a Tesla Model 3, run it with open headers and bring it to a car meet for bragging rights on the most bizzare vehicle.  Like the 10KW 6M amplifier, it wouldn't be street legal, would be pretty dangerous and wouldn't be terribly useful - on the road or on the track.

Says a lot about the owner, too.

Just my 2 cents...

Brian - K6BRN

[KD6VXI]

To the nay-sayers, this is where TUBE amps are going.  And with a life expectancy of 30K hours of continuous operation, if the new owner is 30 years old he will never need to replace the tube in his lifetime. 

Giving a 30 year-old a 10KW 6M high voltage amplifier built on the cheap out of surplus parts is a little like giving a 14-year-old a rusty WWII surplus grenade launcher and saying "Have at it!" in a busy neighborhood.

It this REALLY a good idea?  What will it really be used for?  And given the infrastructure needed to support it (antenna+feedline+power for 10 KW) and its lack of band agility, how useful IS it, really?

It'd be more interesting to shoehorn a Viper V10 into a Tesla Model 3, run it with open headers and bring it to a car meet for bragging rights on the most bizzare vehicle.  Like the 10KW 6M amplifier, it wouldn't be street legal, would be pretty dangerous and wouldn't be terribly useful - on the road or on the track.

Says a lot about the owner, too.

Just my 2 cents...

Brian - K6BRN

Almost everything Dr Alex sells is called Surplus.  As in, Army Navy Surplus.  It would more accurately be described as New, Old Stock (NOS).  I've bought parts from him over a 20 year period. 

A 30 year old can be killed by the voltage in an AL811, an AL1500 or by plugging in a vacuum with a bad cord.  I think your analogy is a bit flawed.

--Shane
WP2ASS / ex KD6VXI

[K6BRN]

Shane :

A 30 year old can be killed by the voltage in an AL811, an AL1500 or by plugging in a vacuum with a bad cord.  I think your analogy is a bit flawed.  --Shane  WP2ASS / ex KD6VXI

Nothing in life is perfect, but I'd call an order of magnitude difference in output with a commensurate increase in high voltage and RF risks very significant.

Not that you'd care or agree, but I'd guess that a court of law just might hold you accountable for handing that fabulous and dangerous toy to a user who gets hurt or hurts others in using it.  There are precedents, at least in the States, for exactly this.  Hope you have a written contract with explicit liability clauses in it, from the purchaser.  Even then, you likely have some exposure.

Brian - K6BRN

[KB8VUL]

Shane :

A 30 year old can be killed by the voltage in an AL811, an AL1500 or by plugging in a vacuum with a bad cord.  I think your analogy is a bit flawed.  --Shane  WP2ASS / ex KD6VXI

Nothing in life is perfect, but I'd call an order of magnitude difference in output with a commensurate increase in high voltage and RF risks very significant.

Not that you'd care or agree, but I'd guess that a court of law just might hold you accountable for handing that fabulous and dangerous toy to a user who gets hurt or hurts others in using it.  There are precedents, at least in the States, for exactly this.  Hope you have a written contract with explicit liability clauses in it, from the purchaser.  Even then, you likely have some exposure.

Brian - K6BRN

Well, by your analogy, you technically CAN fix stupid.  Because there are Darwin Awards (look it up).  No matter the number of interlocks, and safety measures you deploy in a device of this nature, if the end user is dumb enough to bypass them and reach for the tube while the power supply is on, then their stupid gets fixed before they even come into contact with the tube.  Seven kilovolts will come out to meet you.  You don't even need to actually fully come into contact with it.  And as long as you slapped a sticker on that box stating lethal voltage inside, you are covered.  I am not saying there are not people that are that dumb.  But you would need to find 12 more mouth breathers that were just that dumb to sit a jury and find you liable for the death of one of their own.  At some point a person has to take personal responsibility for their actions.  And as far as injury to others, we actually answer questions in our ham tests pertaining to RF exposure.  So if some clown is pointing a 20 foot dish at the neighbors house and pumping 4KW into it, they legally know better, and a good defense attorney will recognize this and argue it was the decision of a 'knowledgeable' person that was tested on the subject matter and get you out of any liability for the end users dumb. 

[W9FIB]

When I first got hired to work on 4160V variable speed drives, our group spent 3 days in safety training and proper design methods for that voltage. And even then, our first prototype took out part of the grid in the industrial park when it blew up. Those voltages are both lethal and extremely dangerous. Even the tiniest mistake can cause death by electrocution, fire, or explosion.

I was always going to build a big amp for VHF/UHF contesting with tubes. I even have a 5kVA 4160 transformer sitting in my shed waiting for that day. Well with the cost reduction and increasing availability of LDMOS, no way I will ever mess with HV anymore. Something about being at less than 100VCD is really appealing. But still need safe practices. 50v @ 50A can do welding.

[KD6VXI]

Having been wacked by 6.2kv on a homebrew amplifier (I didn't build it), I know very real what the repercussions are.  A month shy of a year I found myself in the hospital with heart issues.  45 days later my cardiologist closed up his practice on an emergency basis and had my wife drive me to the ER.  Emergency heart surgery.  Another surgery the next day.

I doubt the severity of the legal repurcussions.  After all, when I bought a Henry, new in Los Angeles, I didn't have to sign any contracts, there where no disclaimers other than Lethal Voltages Present on the amp itself, etc.  Ameritron, I've fixed a few of them, never saw anything more than the same with my Henry.  Same goes for Amp Supply, Commander, etc.  After all, this is a technical hobby and we are at least self trained.  Build a CB amp, different story.  Sell a CBer an amp, different story.

As to your "Not that you'd care or agree,"...  Don't expect much better from you.

--Shane
WP2ASS ex KD6VXI

[K6BRN]

Hi Shane:

Your decisions are yours alone, and so are the consequences of irresponsibility.  The 1.5 KW Henry you once purchased is in-family to this hobby, a 10 KW 6M amplifier is not.

My XYL is an attorney who practiced liability for years and whose specialty was electrocution cases.  She's standing behind me shaking her head right now.  You might want to go back and read W9FIB's post on the topic.

Regarding "being able to fix stupid"... Death is not a fix, its a failure.  Which is why we have railings on stairways.  To make mistakes as recoverable as possible, without anyone being seriously injured.

Regarding your heart issues - you have my sympathies.  That's nothing to take lightly.  Glad you survived and I wish you many years of good health.

Brian - K6BRN

[VR2AX]

Some places EMF compliance 'guidelines' (aka..) will impose a limit lower than the basic power limit, likely to be more significant as you get into the V/UHF range (including 6/4 metres).

True.  But that's all based on average PO, and averaged over time.

UK looks like that at first blush, but the regulator (OFCOM) is refining its 'maths' -- power is based on maximum EIRP within rolling 6 minute periods (admittedly a sort of 'average'), establishment of an 'exclusion zone', more to come.

https://rsgb.org/main/technical/emc/emf-exposure/